Intravascular fluid movement devices, systems, and methods of use

ABSTRACT

An intravascular fluid movement device that includes an expandable member having a collapsed, delivery configuration and an expanded, deployed configuration, the expandable member having a proximal end and a distal end, a rotatable member disposed radially and axially within the expandable member, and a conduit coupled to the expandable member, the conduit at least partially defining a blood flow lumen between a distal end of the conduit and a proximal end of the conduit, the conduit disposed solely radially inside of the expandable member in a distal section of the expandable member.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/US2018/036506, filed Jun. 7, 2018; which application claims priorityto the following U.S. Provisional Patent Applications, all which areincorporated by reference herein: App. No. 62/516,296, filed Jun. 7,2017, and App. No. 62/542,488, filed Aug. 8, 2017.

INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

BACKGROUND

Patients with heart disease can have severely compromised ability todrive blood flow through the heart and vasculature, presenting forexample substantial risks during corrective procedures such as balloonangioplasty and stent delivery. There is a need for ways to improve thevolume or stability of cardiac outflow for these patients, especiallyduring corrective procedures.

Intra-aortic balloon pumps (IABP) are commonly used to supportcirculatory function, such as treating heart failure patients. Use ofIABPs is common for treatment of heart failure patients, such assupporting a patient during high-risk percutaneous coronary intervention(HRPCI), stabilizing patient blood flow after cardiogenic shock,treating a patient associated with acute myocardial infarction (AMI) ortreating decompensated heart failure. Such circulatory support may beused alone or in with pharmacological treatment.

An IABP commonly works by being placed within the aorta and beinginflated and deflated in counterpulsation fashion with the heartcontractions to provide additive support to the circulatory system.

More recently, minimally-invasive rotary blood pumps have been developedthat can be inserted into the body in connection with the cardiovascularsystem, such as pumping arterial blood from the left ventricle into theaorta to add to the native blood pumping ability of the left side of thepatient's heart. Another known method is to pump venous blood from theright ventricle to the pulmonary artery to add to the native bloodpumping ability of the right side of the patient's heart. An overallgoal is to reduce the workload on the patient's heart muscle tostabilize the patient, such as during a medical procedure that may putadditional stress on the heart, to stabilize the patient prior to hearttransplant, or for continuing support of the patient.

The smallest rotary blood pumps currently available can bepercutaneously inserted into the vasculature of a patient through anaccess sheath, thereby not requiring surgical intervention, or through avascular access graft. A description of this type of device is apercutaneously-inserted ventricular assist device (“pVAD”).

There is a need to provide additional improvements to the field of pVADsand similar blood pumps for treating compromised cardiac blood flow.Current pVADs that are designed to add to or replace cardiac output canbe undesirably large for insertion into the patient's blood vessels(e.g., requiring a large femoral artery access sheath or cutdown thatincreases the complication rate after the procedure), provideinsufficient blood flow or create a significant amount of hemolysisdamage to the blood cells, which can lead to adverse outcomes and insome cases death.

There is a need for improvements to pVAD or similar devices to minimizethe insertion profile, thus minimizing procedure complicationsassociated with vascular access, to maximize the flow of blood createdor assisted by the devices, to minimize blood hemolysis and thrombosis,and to facilitate the procedure steps that physicians and their staffneed to manage during use of the product.

In one aspect, there is a need for smaller delivery profile devices thatcan be inserted through access sheaths optionally less than 12 FR, suchas 8 FR or 9 FR, and that can also pump blood flow in the range of 3.5to 6.0 L/min, such as 4.0 to 5.0 L/min, for example, at approximately 60mmHg of head pressure. Because higher rotary pump impeller speeds areknown to increase the risk of hemolysis, in one aspect there is a needfor a pump that can provide sufficient flow at rotational speedssignificantly less than the 50,000 rpm speed that some pVAD pumpsemploy. These needs and other problems with existing approaches areaddressed by the disclosure herein.

SUMMARY OF THE DISCLOSURE

The disclosure is related to medical devices that are adapted to, whenin use, move fluid such as a blood.

One aspect of the disclosure is an intravascular blood pump including anexpandable member having a collapsed, delivery configuration and anexpanded, deployed configuration, the expandable member having aproximal end and a distal end; an impeller disposed radially and axiallywithin the expandable member; and a conduit coupled to the expandablemember, the conduit at least partially defining a blood flow lumenbetween a distal end of the conduit and a proximal end of the conduit,and wherein the conduit disposed solely radially inside of theexpandable member in a distal section of the expandable member.

A proximal section and the distal section of the expandable member caneach have outermost dimensions that are greater than an outermostdimension of a central region of the expandable member that is disposedaxially in between the proximal and distal sections.

A distal end of the conduit can have a configuration that is flaredoutward. A proximal end of the conduit may not have a flaredconfiguration.

The blood pump can further comprise a drive cable in operablecommunication with the impeller.

The blood pump can further include a plurality of distal centeringstruts that are coupled to the expandable member and extend around thedrive cable distal to the impeller, and a plurality of proximalcentering struts that are coupled to the expandable member and extendaround the drive cable proximal to the impeller.

In some instances, the conduit can be non-permeable, semi-permeable, oreven porous.

The expandable member can comprise a plurality of elongate elements thatdefine a plurality of apertures.

The conduit can be disposed radially within the expandable member fromthe proximal end of the conduit to the distal end of the conduit.

The conduit, where it is disposed solely radially inside of theexpandable member, can be radially spaced away from the expandablemember with a gap between the conduit and the expandable member.

The conduit can also be disposed radially outside of the expandablemember in a proximal region of the expandable member.

One aspect of the disclosure is an intravascular fluid pump with aworking portion with a deployed configuration. The working portionincludes a distal expandable member with a collapsed deliveryconfiguration and a deployed configuration, the distal expandable memberhaving a proximal end and a distal end, a distal impeller disposedradially within the distal expandable member; a proximal expandablemember with a collapsed delivery configuration and a deployedconfiguration, the proximal expandable member having a proximal end anda distal end, the distal end of which is axially spaced from theproximal end of the distal expandable member; a proximal impellerdisposed radially within the proximal expandable member, the proximalimpeller spaced proximally from the distal impeller; a conduit extendingaxially between the proximal end of the distal expandable member and thedistal end of the proximal expandable member, the conduit at leastpartially defining a blood flow lumen between a distal end of theconduit and a proximal end of the conduit, wherein a central region ofthe conduit spans an axial distance, and the distal expandable memberand the proximal expandable member do not extend axially into thecentral region, wherein the distal end of the distal expandable memberextends further distally than the distal end of the conduit, and theproximal end of the proximal expandable member extends furtherproximally than the proximal end of the conduit; and an elongate portionextending proximally from the working portion.

The conduit can be coupled to the distal expandable member and theproximal expandable member.

The working portion can further include a central tubular element thatis coupled to the expandable members, wherein the central tubularelement is disposed in the lumen and is disposed between the proximaland distal expandable members. The distal end of the proximal expandablemember can be coupled to a proximal end of the central tubular element,and the proximal end of the distal expandable member can be coupled to adistal end of the central tubular element, the central tubular elementcan extend between the proximal and distal expandable members. Thecentral tubular element can have the same outermost dimension in boththe collapsed and deployed configurations.

The proximal and distal impellers can optionally be driven by a commondrive mechanism, such as a common drive cable that can be coupled to theproximal impeller and to the distal impeller. A common drive mechanismcan define a lumen, which can optionally be used as a guidewire lumen.

A common drive cable can include a first section coupled to a secondsection with the second section adjacent the first section, the firstand second sections having a common longitudinal axis and a common outerdimension measured orthogonally relative to the common axis, wherein thefirst section is stiffer than second section, and either the distalimpeller or the proximal impeller is coupled to the first section. Thefirst section can include a first tubular member and the second sectioncan include a wound member. The drive cable can further include a thirdsection adjacent the second section, the third section being coupled tothe other of the distal impeller and the proximal impeller.

The proximal and distal impellers can be in operative communication witha common motor.

The distal expandable member can be coupled to a distal bearing and to aproximal bearing, wherein a drive mechanism extends through the distaland proximal bearings.

The proximal expandable member can be is coupled to a distal bearing andto a proximal bearing, wherein a drive mechanism extends through thedistal and proximal bearings.

The distal expandable member can comprise a plurality of elongatesegments disposed relative to one another to define a plurality ofapertures, wherein at least a portion of one of the plurality ofapertures is distal to the distal end of the conduit, defining at leastone blood inlet aperture to allow blood to enter the lumen. The proximalexpandable member can comprise a plurality of elongate segments disposedrelative to one another to define a second plurality of apertures,wherein at least a portion of one of the second plurality of aperturesis proximal to the proximal end of the conduit, defining at least oneoutlet aperture to allow blood to exit the lumen.

At least one of the distal and proximal expandable members has aplurality of elongate segments that are braided.

The conduit is optionally impermeable, optionally semi-permeable, andoptionally porous.

The conduit can be made of material such that, in the central regionaxially between the distal and proximal expandable members, the materialis adapted to deform radially inward more easily than the expandablemembers in response to radially inward forces on the working portion.

The conduit can be coupled to the proximal expandable member at alocation along the proximal expandable member with a greatest radialdimension measured orthogonally relative to a longitudinal axis of theproximal expandable member, and the conduit can be coupled to the distalexpandable member at a location along the distal expandable member witha greatest radial dimension measured orthogonally relative to alongitudinal axis of the distal expandable member.

The conduit, at a location where it is coupled to the proximalexpandable member, can be disposed radially within the proximalexpandable member, and the conduit, at a location where it is coupled tothe distal expandable member, can be disposed radially within the distalexpandable member. The conduit, at a location where it is coupled to theproximal expandable member, can also be disposed radially outside of theproximal expandable member, and the conduit, at the location where it iscoupled to the distal expandable member, can also be disposed radiallyoutside of the distal expandable member. The proximal expandable membercan have a distal section that tapers radially inward and distally, andthe distal expandable member can have a proximal section that tapersradially inward and proximally, and wherein the conduit can be disposedsolely radially outside of the proximal expandable member at a firstlocation in the distal section and not coupled directly to the proximalexpandable member at the first location, and wherein the conduit can bedisposed solely radially outside of the distal expandable member at asecond location in the proximal section and not coupled directly to thedistal expandable member at the second location.

A distal end of the distal impeller, in the expanded configuration maynot extend further distally than a distal end of the conduit.

A proximal end of the proximal impeller, in the expanded configuration,may not extend further proximally than a proximal end of the conduit.

The conduit can be flexible, and may optionally be conformable.

The proximal impeller may extend further proximally than a proximal endof the conduit in the deployed configuration.

The distal impeller may extend further distally than a distal end of theconduit in the deployed configuration.

A first portion of the conduit can be disposed solely radially outsideof the proximal expandable member, and a second portion of the conduitthat is proximal to the first portion of the conduit can be disposedradially inside the proximal expandable member. The first portion of theconduit can be distal to a distal end of the proximal impeller.

A first portion of the conduit can be disposed solely radially outsideof the distal expandable member, and wherein a second portion of theconduit that is distal to the first portion of the conduit can bedisposed radially inside the distal expandable member. The first portionof the conduit can be proximal to a proximal end of the distal impeller.

One aspect of the disclosure is related to methods of deploying anintravascular blood pump across a valve such as an aortic valve.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A, 1B, 1C, 1D and 1E illustrate merely exemplary exteriorprofiles for working portions of medical devices herein.

FIG. 2A is a side view of an exemplary working portion, which includesan expandable member, and impeller, and a conduit.

FIG. 2B is a close-up view of a portion of the view from FIG. 2A.

FIG. 3A is a side view of an exemplary working portion where a portionof a conduit is solely radially within an expandable member.

FIG. 3B is a side view of an exemplary working portion that includes animpeller.

FIGS. 4A and 4B illustrate an exemplary placement of the device fromFIG. 3B.

FIG. 5 is a side view of an exemplary working portion.

FIGS. 6A, 6B and 6C illustrate at least a portion of an exemplaryworking portion.

FIGS. 7A-7E illustrate at least a portion of an exemplary workingportion.

FIGS. 8A-8F illustrate at least a portion of an exemplary workingportion.

FIG. 9 illustrates at least a portion of an exemplary medical devicethat has a working portion.

FIG. 10 illustrates at least a portion of an exemplary medical devicethat has a working portion.

FIG. 11 illustrates at least a portion of an exemplary medical devicethat has a working portion.

FIG. 12 illustrates at least a portion of an exemplary medical devicethat has a working portion.

FIG. 13A illustrates at least a portion of an exemplary medical devicethat has a working portion, where at least two different impellers canbe rotated at different speeds.

FIG. 13B illustrates at least a portion of an exemplary medical devicethat has a working portion, where at least two different impellers canbe rotated at different speeds.

FIG. 13C illustrates at least a portion of an exemplary medical devicethat has a working portion with at least two impellers with differentpitches.

FIG. 14 illustrates at least a portion of an exemplary medical devicethat has a working portion.

FIGS. 15A-15D are end views showing exemplary outer profiles ofexemplary working portions in use.

FIG. 16 is a side view of an exemplary working portion that includes aconduit, a plurality of impellers, an expandable member

FIG. 17 is a side view of an exemplary working portion that includes aconduit, a plurality of impellers, and a plurality of expandablemembers.

FIGS. 18A, 18B, 18C and 18D illustrate an exemplary working portion thatincludes a conduit, a plurality of impellers, and a plurality ofexpandable members.

FIG. 19 illustrates an exemplary placement of a working portion, theworking portion including a conduit, a plurality of expandable members,and a plurality of impellers.

FIGS. 20A, 20B, and 20C illustrate exemplary distal end constructionsand configurations for working portions.

FIG. 21A illustrates an exemplary position of a deployed workingportion.

FIGS. 21B and 21C illustrate exemplary distal regions of a workingportion.

FIGS. 22A and 22B illustrate end views of an exemplary impeller, withblades in collapsed configurations (FIG. 22A) and expandedconfigurations (FIG. 22B).

FIGS. 23A-C illustrate an exemplary impeller.

FIGS. 24A and 24B illustrate an exemplary impeller.

FIGS. 25A and 25B illustrate an exemplary multi-lumen working portion ina collapsed, delivery configuration (FIG. 25A) and an expandedconfiguration (FIG. 25B).

FIGS. 26A and 26B illustrates an exemplary multi-lumen design for aworking portion, showing deployed and expanded configurations,respectively.

FIGS. 27A-C illustrate exemplary embodiments of a working portion withat least one additional lumens.

FIG. 28 illustrates an exemplary working portion.

FIG. 29 illustrates an exemplary fluid movement medical device,including a working portion.

FIG. 30 illustrates an exemplary magnetic coupling for a motor and drivecable.

FIG. 31 illustrates an embodiment of a 90-degree gearset.

FIG. 32A illustrates an exemplary working portion including a lumenregion and a distal tip in a generally straight configuration.

FIG. 32B shows an internal elongate member, such as a guidewire,advanced through the working portion and into a distal tip. Thepreviously straight tip durably assumes a different configuration.

FIGS. 33A, 33B, 33C, 33D and 33E illustrate exemplary distal ends ofexemplary working portions.

FIG. 34 illustrates an exemplary working portion.

FIG. 35 illustrates an exemplary embodiment of an impeller.

FIG. 36 shows an exemplary pump console with display.

DETAILED DESCRIPTION

The present disclosure is related to medical devices, systems, andmethods of use and manufacture. Medical devices herein may include adistal working portion adapted to be disposed within a physiologicvessel, wherein the distal working portion includes one or morecomponents that act upon fluid. For example, distal working portionsherein may include one or more rotating members that when rotated, canfacilitate the movement of a fluid such as blood.

Any of the disclosure herein relating to an aspect of a system, device,or method of use can be incorporated with any other suitable disclosureherein. For example, a figure describing only one aspect of a device ormethod can be included with other embodiments even if that is notspecifically stated in a description of one or both parts of thedisclosure. It is thus understood that combinations of differentportions of this disclosure are included herein unless specificallyindicated otherwise.

FIGS. 1A-1E illustrate exemplary exterior profiles (i.e., outerconfiguration) for working portions (described in more detail below) ofmedical devices that extend across, or cross, a valve such as an aorticvalve. Only a portion of the elongate proximal portions are shown, whichextend proximally from the working portions. The relative positions ofan aortic valve, ascending aorta, and left ventricle, are shown. FIG. 1Aillustrates an exemplary embodiment in which a medical device includesworking portion 100 that has a generally cylindrical (i.e., not a truecylinder but closely resembling a cylinder such that one of ordinaryskill in the art would understand it to be considered to be cylindrical)expanded configuration, with a central region that spans a valve havingthe greatest outer dimension (measured orthogonally relative tolongitudinal axis LA, shown only in FIG. 1A for simplicity), and whereinthe outer dimension gets smaller in the proximal and distal directions.The working portion is sized such that a distal end is disposed in theleft ventricle when a proximal end is disposed in the ascending aorta.

When a working portion is expanded at the location of a valve, theworking portion may contact the valve leaflets (regardless of whetherthey are native leaflets or part of a replacement heart valve) and maycause damage to them when the leaflets are pressed against the workingportion during heart pumping and to facilitate closure of an effectivevalve seal against the working portion. It may thus be advantageous tominimize or reduce the profile of the working portion at the locationwhere it crosses or spans the valve (e.g., aortic) to minimize damage tothe valve leaflets. FIGS. 1B-1E illustrate exemplary working portionconfigurations that have central regions with reduced profile dimensionsand can be positioned at the location of a valve to reduce thelikelihood of valve damage.

FIG. 1B shows an exemplary working portion that has a generallycylindrical expanded configuration as shown, and is sized such that adistal region is in the ventricle when a proximal region is in theascending aorta. A central region of the working portion spans thevalve. The expanded outer configuration is generally cylindrical.

FIG. 1C shows an exemplary working portion in an expanded configurationin which a distal region of the working portion expands to a greaterouter dimension than a proximal region of the working portion. The outerdimension becomes substantially smaller (e.g., at least half as much) atthe location of the valve and extending proximally.

FIG. 1D shows an exemplary working portion in an expanded configurationin which a proximal region of the working portion (which is disposed inthe ascending aorta) expands to a greater outer dimension than a distalregion of the working portion. The outer dimension becomes substantiallysmaller (e.g., at least half as much) at the location of the valve andextending distally.

FIG. 1E shows an exemplary working portion in an expanded configurationin which a proximal region and a distal region are configured to expandto a greater dimension that a central region, wherein the central regionis disposed between the proximal and distal regions. The central regioncan have an outer dimension that is half as much or less than either orboth of the proximal and distal regions. The working portion in FIG. 1Ecan be thought of as having a general dumbbell configuration whenexpanded.

In alternative embodiments, the working portion can have a generallyuniform collapsed delivery profile, and is configured to expand to agenerally uniform expanded larger profile. “Uniform” may refer todimensions in this context of varying no more than 10%.

FIGS. 2A and 2B illustrate an exemplary fluid pump working portion thatincludes impeller 26 that is disposed radially within an expandablemember. FIGS. 2A and 2B show the working portion configuration when itis expanded extracorporeally. The expandable member includes distalregion 21, central region 22, and proximal region 23. Distal region 21and proximal region 23 have larger outer dimensions than central region22, and the expandable member can be thought of as having a dumbbellconfiguration. In use, central region 22, or at least a portion of it,can be positioned across a valve. The proximal and distal regions 23 and21, respectively, have tapered end regions that taper down from a largerouter dimension in more central regions. Impeller 26 is disposedradially within proximal region 23, and a short portion of impeller 26may also extend slightly within central region 22. Elongate shaft 28,which can be a drive shaft or drive cable, is coupled to impeller anddrives the rotation of impeller 26 when activated (e.g., by a motor).Centering struts 29 (four of which are shown) are disposed at the endsof impeller 26, and extend around and function to center the shaft 28.Struts 29 are coupled to the expandable member and extend around shaft28 to stabilize it. Two struts 29 at each end define an aperture throughwhich shaft 29 extends. By centering the shaft 28, the struts 29 alsocenter the impeller 26 within the expandable member and prevent theimpeller blades from engaging the expandable member when they arerotating.

Working portion 20 also includes conduit 25 that is coupled to theexpandable member. Conduit 25 extends from a location within distalregion 21 to a location within proximal region 23, but does not extendto the distal and proximal ends of the expandable member. The conduitacts and is configured and made of material(s) that create a fluid lumentherein between an inflow region and an outflow end region. Flow intothe inflow region is labeled “I,” and flow out at the outflow region islabeled “O.” The expandable member includes a plurality of elongatemembers that together define a plurality of apertures through whichfluid can flow at the inflow and outflow regions. Any of the conduitsherein can be impermeable. Any of the conduits herein can alternativelybe semipermeable. Any of the conduits herein may also be porous, butwill still define a fluid lumen therethrough. In some embodiments theconduit is a membrane, or other relatively thin layered member. In thisembodiment conduit 25 is coupled to an exterior of the expandablemember. The distal end of working portion has a large open surface areathat permits sufficient blood inlet flow even if it is pushed against(i.e., contacting) an inner surface of a hollow anatomical structuresuch as, for example, a left ventricle of the heart. The proximal regionof conduit 25 opens as an impeller shroud to permit efficient axial pumpflow.

Any of the conduits herein, unless indicated to the contrary, can besecured to an expandable member such that the conduit, where is itsecured, can be radially inside and/or outside of the expandable member.For example, a conduit can extend radially within the expandable memberso that inner surface of the conduit is radially within the expandablemember where it is secured to the expandable member.

FIG. 2A is an example of a working portion in which the conduit hasflared distal and proximal regions, due to the configuration of theexpandable member, as well as how far along (axially) the expandablemember the conduit extends. FIG. 2A is also an example of a workingportion with distal and proximal regions that are larger in outerdimension than a central region.

In alternative embodiments, the distal region of the conduit has aflared configuration like a trumpet bell to reduce the work energyrequired for fluid to enter the inlet region.

The expandable member can be constructed of a variety of materials andin a variety of ways. For example, the expandable member may have abraided construction, or it can be formed by laser machining. Thematerial can be deformable, such as nitinol. The expandable member canbe self-expanding or can be adapted to be at least partially activelyexpanded.

The working portion in FIG. 2A can be adapted to be collapsible to alower profile delivery configuration. The expandable member and impellercan be adapted to be collapsed to the delivery configuration. Theconduit collapses with the expandable member due to its coupling withthe expandable member. FIG. 2B illustrates a portion of the view fromFIG. 2A, showing components amplified for clarity.

When the impeller is activated to rotate, the rotation pulls fluid intothe inflow end, through the lumen defined by the conduit, and out of theoutflow end.

In some embodiments, the expandable member is adapted to self-expandwhen released from within a containing tubular member such as a deliverycatheter, a guide catheter or an access sheath. In some alternativeembodiments, the expandable member is adapted to expand by activeexpansion, such as action of a pull-rod that moves at least one of thedistal end and the proximal end of the expandable member toward eachother.

FIG. 3A illustrates an exemplary working portion 30 that is similar tothat shown in FIGS. 2A and 2B. Components that are the same as inworking portion 20 are not labeled for clarity, but are incorporatedinto this figure. Working portion 30 includes conduit 31 that includesdistal region 32, central region 34, and proximal region 33. Thisembodiment differs from working portion 20 in FIG. 2A in that conduitdistal region 32 is radially within the expandable member and is notattached directly to a portion of distal region 32. In the case of aworking portion that is located across the aortic valve, for instance,this arrangement near the distal end of the expandable member allows fornative cardiac ejection blood flow to go around (radially outside of)the more distal end of the conduit and through the aortic valve that isdisposed adjacent to the conduit. Conduit 31 transitions from outside toinside the expandable member between the ends of the expandable member,and in this embodiment it transitions in a central region of theexpandable member that has a reduced outer dimension.

FIG. 3B illustrates an exemplary working portion that is similar to thatshown in FIGS. 2A and 3A. Parts that are the same are not re-labeled forclarity, but are incorporated into this figure. In FIG. 3B, workingportion 40 has a conduit that extends radially within the expandablemember, including distal region 41, central region 42 and proximalregion 43. In distal region 41, there is a region where the conduit issolely radially within the expandable member, and not attached thereto,as shown. In the method of use that positions the working portion acrossthe aortic valve, for instance, this arrangement near the proximal endof the expandable member allows for more native cardiac ejection bloodflow that goes around (radially outside of) the conduit distal end andthrough the aortic valve adjacent to the conduit to enter the left andright main coronary arteries without obstruction by the conduit.

The fluid movement devices, system and methods herein can be used andpositioned in a variety of locations within a body. While specificexamples may be provided herein, it is understood that that the workingportions can be positioned in different regions of a body than thosespecifically described herein.

FIGS. 4A and 4B show an exemplary working position of working portion 40from FIG. 3B. Working portion 40 has been deployed to a deployedconfiguration and extends across an aortic valve, which includes aorticvalve leaflets “VL.” The expandable member distal region 21 ispositioned in a left ventricle “LV,” central region 22 extends acrossthe valve, and proximal region 23 is positioned in the ascending aorta.A distal end of the proximal region 23 engages the leaflets as well, asis shown. The proximal region 23 has a configuration and size, relativeto the opening of the valve, that prevent the proximal region 23 frompassing through the valve, ensuring that the outflow opening(s) remainin the ascending aorta. Distal region 21 also has a configuration andsize that prevents distal region 21 from passing through the aorticvalve, ensuring that the blood inflow port(s) remain within the leftventricle (see FIG. 4B). As can be seen, the working portion has alength between the blood inflow and the blood outflow ports that ensuresthat the blood outflow port(s) are located within the ascending aortawhen the blood inflow port(s) are disposed within the left ventricle.

This disclosure also includes working portions that include a pluralityof impellers.

FIG. 5 illustrates an exemplary working portion 200 of a medical devicethat includes a proximal impeller (with blades 201) in communicationwith first motor 202, and a distal impeller (with blades 201′) incommunication with second motor 202′. By incorporating two motors intothe fluid pump, the available torque can be doubled while maintainingthe same maximum diameter as a single motor. This can help reduce theprofile of the device. In the push-pull embodiment shown in FIG. 5,proximal motor 202 pulls blood through the working portion (whichgenerally includes a reinforced elongate body 213, such as acoil-reinforced polymer or a braid-reinforced polymer, for examplewithout limitation) while distal motor 202′ pushes blood through theworking portion. When used for left ventricle assistance, the aorticvalve would be placed between the blood inflow ports 207 and the bloodoutflow ports 208. Elongate body 213 has inflow apertures 207 on aradially outer portion of body 213, and outflow apertures 208 on aradially outer portion of body 213. The arrows show the direction ofblood flowing through the apertures, with “distal” being on the right ofthe page.

FIGS. 6A-6C illustrate an exemplary embodiment of working portion 300 inwhich proximal motor 302 pulls blood through the working portion (whichcan include a reinforced body 313 such as a coil-reinforced polymer or abraid-reinforced polymer, for example) while distal motor 302′ pushesblood through the working portion via expandable side lumen 311.Proximal motor 302 controls and causes rotation of proximal impeller301, and distal motor 302′ controls and causes rotation of distalimpeller 301′. Apertures 307 and 308 in the working portion are labeled.Expandable side lumen 311 can be expanded using mechanical techniques,such as, for example without limitation, deploying an expandablegenerally braided structure, or simply by inflation of the side lumen bythe increased pressure generated by the distal impeller 301.′ Theworking portion also includes inlet aperture 307 at the distal region.Side lumen 311 can be configured to expand to one side of elongate body313, which would create a non-circular profile to the exterior of thecatheter, or, as shown in the alternative FIG. 6C cross-section, itcould expand more generally encircling the main reinforced catheter. Atleast a portion of space along a side of the reinforced body should beleft exposed (e.g., one of inlet ports 307) to allow blood inflow intobody 313 to support inflow to the proximal motor 302 and impeller 301.When in use for left ventricle assistance, the aortic valve could beplaced between the two sets of blood inflow ports 307 and the bloodoutflow ports 308.

FIGS. 7A-7E illustrate another exemplary embodiment of a working portion(400) with a plurality of impellers. In this pull-pull embodiment, twoimpellers each pull blood through a lumen of the working portion andpush the blood through side-exiting exit holes, as shown by the arrowsindicating flow. Apertures 407 are inflow apertures, and outflowapertures 408 are outflow apertures. Because these impellers draw arelative vacuum to convey the blood, the lumens should be reinforced toprevent or minimize collapse. FIGS. 7B-7E illustrate the sectional viewsshown in FIG. 7A, respectively, and are underneath the section fromwhich they are taken. The embodiment in FIGS. 7A-7E show a primary lumen413 in which the motors and impellers are coaxially located. Primarylumen 413 may be coil-reinforced or braid- or similarstructure-reinforced. Secondary lumen 411 expands outward from primarylumen 413, such as by an expanding braid, stent or basket-like design,similar to the secondary lumen in 311 in FIGS. 6A-6C. Blood inflow isnear the distal end of the working portion. Distal motor 402′ andimpeller 401′ drive blood to exit from at least side holes 408 that areadjacent or near the impeller 401′, which can be seen in thecross-sectional view B-B of FIG. 7C showing crescent-shaped outer lumen411 above the exit hole 408. The proximal motor 402 and impeller 401drive blood to exit from side holes 408 adjacent or near the proximalimpeller 401.

FIGS. 8A-8F illustrate another exemplary embodiment of a working portion(500) that includes a plurality of impellers, 500 and 501′, with thearrows indicating direction of flow. In this push-push embodiment, theworking portion 500 includes dual motors and impellers arranged in apush-push configuration, where each impeller pushes blood through alumen of the working portion (511 or 513) and pushes the blood throughside-exiting apertures or proximal-end-exiting apertures 508. Becausethese impellers create pressure to convey the blood, the lumens 511 and513 do not necessarily need to be reinforced to prevent collapse and theouter lumen 511 can be fluid-inflated by pump-elevated blood pressure.This embodiment shows primary lumen 513 in which the motors andimpellers are coaxially located. Primary lumen 513 may becoil-reinforced or braid- or similar structure-reinforced, for example.Secondary lumen 511 can expand outward as any of the secondary lumensabove, or by fluid-inflation from pump-elevated blood pressure. Bloodinflow is near the distal end of the working portion. Both lumens 511and 513 exit blood from a proximal portion of the working portion, suchas through side apertures 508, an open braid structure or similar exitpassage. The two impellers 501 and 501′ could be driven by a singlemotor with spindles exiting each end, or, as is shown in FIG. 8F, twomotors 502 and 502′ faced back-to-back and adjacent one another wouldeffectively double the available torque to drive the blood pumping.

FIG. 9 illustrates an exemplary embodiment of a medical device whereinthe working portion (600) includes a plurality of impellers. The medicaldevice includes a remote motor 602 disposed at a proximal end of anelongate portion of the medical device. The remote motor 602 is coupledto drive cable 603, which is coupled to impellers 601 and 601′. Motor602 drives the impellers. By locating the motor remotely, a larger motorcan be used than would fit within a desirably smaller insertablecatheter shaft. Any of the embodiments herein that include a motorwithin the catheter can be modified to instead have one or more remotemotors. Working portion 600 can have a variety of inflow and outflowconfigurations and placements, such as catheter side holes 608 for eachimpeller or either one, or end apertures 607 that allow flow to bemaximized axially instead of radially. The elongate body 604 extendingbetween the impellers can be structurally reinforced such as by, forexample, a wire-coil sandwiched between fused polymer layers, or by agenerally braided structure. Coil-reinforced designs generally havebetter flexibility than braid-reinforced designs, and a high level offlexibility is generally desirable for navigation of the working portioninto position. This embodiment or any other suitable embodiment hereincan also include the remote motor with a catheter handle, or a coupledhandle/hub combination.

FIG. 10 illustrates an exemplary embodiment of a medical device whereinthe working portion (1100) includes a plurality of impellers. Workingportion 1100 includes distal impeller 1101′ coupled to motor 1102′.Working portion 1100 also includes proximal impeller 1101, which iscoupled to remote motor 1102, which are in operable communication viadrive-cable 1103. Distal motor 1102′ is located near the distal end ofthe working portion and drives impeller 1101′ that pushes blood throughthe lumen of the working portion, while remote proximal motor 1102drives cable-driven proximal impeller 1101, which is disposed closer tothe proximal end of the working portion. In use, like with other workingportions herein, working portion 1100 can be positioned so that body1113 crosses a valve (e.g., aortic valve) at a location generallybetween the two impellers.

FIG. 11 illustrates an exemplary embodiment of a medical device whereinthe working portion (1200) includes a plurality of impellers. Workingportion 1200 includes direct-drive proximal motor 1202 coupled toproximal impeller 1201. External motor 1202′ is in operablecommunication with distal impeller 1201′ via drive cable 1203. Drivecable 1203 can be configured within a lumen that extends along andadjacent to internal proximal motor 1202, and then extends into theworking portion lumen, and is directed to be generally centered withinthe lumen so that the distal impeller 1201′ is centered with the lumenof the working portion. Not shown are optional centering elements, suchas, for example without limitation, two pair of a trio of struts thatattach between the outer wall 1213 of working portion and rotationalbearing elements that support the rotating drive cable 1203 so that theimpeller 1201′ is stably centered within the working portion lumen.Exemplary centering struts that can be used are struts 29 in FIGS. 2Aand 2B.

FIG. 12 illustrates an exemplary embodiment of a medical device whereinthe working portion (1300) includes a plurality of impellers. Themedical device includes remote motors 1302 and 1302′, which are inoperable communication with drive cables 1303 and 1303′, respectively.Drive cables 1303 and 1303′ are in operable communication with proximalimpeller 1301 and distal impeller 1301′, respectively, both of which aredisposed within working portion 1300. Drive cables 1303 and 1303′ aredisposed side by side with proximal region 1310, and drive cable 1303′extends along the periphery of the working portion for a distance, thenextends towards the center of the lumen. Centering elements can beincluded as well, such as is described with reference to FIG. 11. Thedrive cables can be in separate lumens in proximal region 1310. Drivecable 1303′ can be in an external lumen or within one or more bearingelements where it extends along the periphery 1316 of the workingportion.

In any of the embodiments herein in which the medical device (1330)includes a plurality of impellers, the device can be adapted such thatthe impellers rotate at different speeds. FIG. 13A illustrates a medicaldevice that includes gearset 1340 coupled to both inner drive member1338 and outer drive member 1336, which are in operable communicationwith distal impeller 1334 and proximal impeller 1332, respectively. Thedevice also includes motor 1342, which drives the rotation of innerdrive member 1338. Inner drive member 1338 extends through outer drivemember 1336. Activation of the motor 1332 causes the two impellers torotate at different speeds due to an underdrive or overdrive ratio.Gearset 1340 can be adapted to drive either the proximal or distalimpeller faster than the other. Any of the devices herein can includeany of the gearsets herein to drive the impellers at different speeds.

FIG. 13B illustrates a portion of an alternative embodiment of a dualimpeller device (1350) that is also adapted such that the differentimpellers rotate at different speeds. Gearset 1356 is coupled to bothinner drive member 1351 and outer drive member 1353, which are coupledto distal impeller 1352 and proximal impeller 1354, respectively. Thedevice also includes a motor like in FIG. 13A. FIGS. 13A and 13Billustrate how a gearset can be adapted to drive the proximal impellerslower or faster than the distal impeller.

In alternative embodiments, a common drive cable or shaft can drive therotation of two (or more) impellers, but the blade pitch of the twoimpellers (angle of rotational curvature) can be different, with thedistal or proximal impeller having a steeper or more gradual angle thanthe other impeller. This can produce a similar effect to having agearset. FIG. 13C shows a portion of a medical device (1360) thatincludes common drive cable 1366 coupled to proximal impeller 1364 anddistal impeller 1362, and to a motor not shown. The proximal impellersherein can have a greater or less pitch than the distal impellersherein. Any of the working portions herein with a plurality of impellerscan be modified to include first and second impellers with differentpitches.

FIG. 14 shows an exemplary alternative embodiment of fluid pump 1370that can rotate first and second impellers at different speeds. Firstmotor 1382 drives cable 1376, which is coupled to distal impeller 1372,while second motor 1384 drives outer drive member 1378 (via gearset1380), which is coupled to proximal impeller 1374. Drive cable 1376extends through outer drive member 1378. The motors can be individuallycontrolled and operated, and thus the speeds of the two impellers can becontrolled separately. This system setup can be used with any systemherein that includes a plurality of impellers.

In use, the working portions wherein may be placed across a delicatestructure such as a valve (e.g., aortic valve). It may be helpful toavoid damage to the valve, and the working portion may be adapted andconstructed to do so. Because the aortic valve (for example, or othersimilar valve) generally closes with three valves meeting near a centralpoint, it may be advantageous for the exterior of any of the workingportions herein to have a non-circular configuration at the locationwhere the working portion crosses, or spans, the valve. It may be lessdesirable for a non-circular catheter body to be rotationally aligned toideally match the aortic valve. FIGS. 15A, 15B and 15C illustrateexemplary outer profile configurations for working portions herein,which can be incorporated into any working portion herein. FIG. 15Dshows a circular outer profile configuration by comparison.

In some embodiments, the working portion can have a compliant orsemi-compliant exterior structure in the region where it crosses thevalve so that the forces of the valve pressing against the workingportion will at least partially deform the exterior structure to atleast partially reduce the reactionary forces applied by the exteriorstructure to the valve. This can help prevent damage to the valve at thelocation where it spans the valve.

It may also be advantageous for the exterior of any of the workingportion to be smooth so that any rubbing of fragile structures such asvalve leaflets will cause minimal damage to those structures. Forexample, a stent-like or similar structure at that region of the valvemay cause high-spots (like a dull cheese-grater) that might cause damageto the valve. Minimizing the height of such protrusions and/orminimizing the distance between them may be beneficial and preventdamage to delicate anatomical structures.

FIG. 16 is a side view illustrating a distal portion of an exemplaryintravascular fluid pump, including working portion 1600, whereinworking portion 1600 includes proximal impeller 1606 and distal impeller1616, both of which are in operable communication with drive cable 1612.Working portion 1600 is in an expanded configuration in FIG. 16, but isadapted to be collapsed to a delivery configuration so that it can bedelivered with a lower profile. The impellers can be attached to drivecable 1612. Drive cable 1612 is in operable communication with anexternal motor, not shown, and extends through elongate shaft 1610.

Working portion 1600 also includes expandable member 1602, which in thisembodiment has a proximal end 1620 that extends further proximally thana proximal end of proximal impeller 1606, and a distal end 1608 thatextends further distally than a distal end 1614 of distal impeller 1616.Expandable member 1602 is disposed radially outside of the impellersalong the axial length of the impellers. Expandable member 1602 can beconstructed in a manner and made from materials similar to many types ofexpandable structures that are known in the medical arts to be able tocollapsed and expanded, examples of which are provided herein.

Working portion 1600 also includes conduit 1604, which is coupled toexpandable member 1602, has a length L, and extends axially between theimpellers. Conduit 1604 creates and provides a fluid lumen between thetwo impellers. When in use, fluid move through the lumen provided byconduit 1604. The conduits herein are non-permeable, or they can besemi-permeable, or even porous as long as they can still define a lumen.The conduits herein are also flexible, unless it is otherwise indicated.The conduits herein extend completely around (i.e., 360 degrees) atleast a portion of the working portion. In working portion 1600, conduitextends completely around expandable member 1602, but does not extendall the way to the proximal end 1602 or distal end 1608 of expandablemember 1602. The structure of the expandable member creates at least oneinlet aperture to allow for inflow “I,” and at least one outflowaperture to allow for outflow “O.” Conduit 1604 improves impellerpumping dynamics, compared to those that working portion 1600 would havewithout the conduit.

Expandable member 1602 can have a variety of constructions, and madefrom a variety of materials, such as any variety of expandable stents orstent-like devices in the medical arts, or any other example providedherein. For example without limitation, expandable member 1602 couldhave an open-braided construction, such as a 24-end braid, although moreor fewer braid wires could be used. An exemplary material for theexpandable member is nitinol, although other materials could be used.Expandable member 1602 has an expanded configuration, as shown, in whichthe outer dimension (measured orthogonally relative a longitudinal axisof the working portion) of the expandable member is greater in at leasta region where it is disposed radially outside of the impellers than ina central region 1622 of the expandable member that extends axiallybetween the impeller. Drive cable 1612 is co-axial with the longitudinalaxis in this embodiment. In use, the central region can be placed acrossa valve, such as an aortic valve. In some embodiments, expandable member1602 is adapted and constructed to expand to an outermost dimension of12-24F (4.0-8.0 mm) where the impellers are axially within theexpandable member, and to an outermost dimension of 10-20F (3.3-6.7 mm)in central region 1622 between the impellers. The smaller central regionouter dimension can reduce forces acting on the valve, which can reduceor minimize damage to the valve. The larger dimensions of the expandablemember in the regions of the impellers can help stabilize the workingportion axially when in use. Expandable member 1602 has a generaldumbbell configuration. Expandable member 1602 has an outerconfiguration that tapers as it transitions from the impeller regions tocentral region 1622, and again tapers at the distal and proximal ends ofexpandable member 1602.

Expandable member 1602 has a proximal end 1620 that is coupled to shaft1610, and a distal end 1608 that is coupled to distal tip 1624. Theimpellers and drive cable 1612 rotate within the expandable member andconduit assembly. Drive cable 1612 is axially stabilized with respect todistal tip 1624, but is free to rotate with respect to tip 1624.

In some embodiments, expandable member 1602 can be collapsed by pullingtension from end-to-end on the expandable member. This may includelinear motion (such as, for example without limitation, 5-20 mm oftravel) to axially extend expandable member 1602 to a collapsedconfiguration with collapsed outer dimension(s). Expandable member 1602can also be collapsed by pushing an outer shaft such as a sheath overthe expandable member/conduit assembly, causing the expandable memberand conduit to collapse towards their collapsed delivery configuration.

Impellers 1606 and 1616 are also adapted and constructed such that oneor more blades will stretch or radially compress to a reduced outermostdimension (measured orthogonally to the longitudinal axis of the workingportion). For example without limitation, any of the impellers hereincan include one or more blades made from a plastic formulation withspring characteristics, such as any of the impellers described in U.S.Pat. No. 7,393,181, the disclosure of which is incorporated by referenceherein and can be incorporated into embodiments herein unless thisdisclosure indicates to the contrary. Alternatively, for example, one ormore collapsible impellers can comprise a superelastic wire frame, withpolymer or other material that acts as a webbing across the wire frame,such as those described in U.S. Pat. No. 6,533,716, the disclosure ofwhich is incorporated by reference herein.

The inflow and/or outflow configurations of working portion 1600 can bemostly axial in nature.

Exemplary sheathing and unsheathing techniques and concepts to collapseand expand medical devices are known, such as, for example, thosedescribed and shown in U.S. Pat. No. 7,841,976 or 8,052,749, thedisclosures of which are incorporated by reference herein.

FIG. 17 is a side view illustrating a deployed configuration(extracorporally) of a distal portion of an exemplary embodiment of afluid movement system. Exemplary system 1100 includes working portion1104 and an elongate portion 1106 extending from working portion 1104.Elongate portion 1106 can extend to a more proximal region of thesystem, not shown for clarity, and that can include, for example, amotor. Working portion 1104 includes first expandable member 1108 andsecond expandable member 1110, axially spaced apart along a longitudinalaxis LA of working portion 1104. Spaced axially in this context refersto the entire first expandable member being axially spaced from theentire second expandable member along a longitudinal axis LA of workingportion 1104. A first end 1122 of first expandable member 1108 isaxially spaced from a first end 1124 of second expandable member 1110.

First and second expandable members 1108 and 1110 generally each includea plurality of elongate segments disposed relative to one another todefine a plurality of apertures 1130, only one of which is labeled inthe second expandable member 1110. The expandable members can have awide variety of configurations and can be constructed in a wide varietyof ways, such as any of the configurations or constructions in, forexample without limitation, U.S. Pat. No. 7,841,976, or the tube in U.S.Pat. No. 6,533,716, which is described as a self-expanding metalendoprosthetic material. For example, without limitation, one or both ofthe expandable members can have a braided construction or can be atleast partially formed by laser cutting a tubular element.

Working portion 1104 also includes conduit 1112 that is coupled to firstexpandable member 1108 and to second expandable member 1110, and extendsaxially in between first expandable member 1108 and second expandablemember 1110 in the deployed configuration. A central region 1113 ofconduit 1112 spans an axial distance 1132 where the working portion isvoid of first and second expandable members 1108 and 1110. Centralregion 1113 can be considered to be axially in between the expandablemembers. Distal end 1126 of conduit 1112 does not extend as far distallyas a distal end 1125 of second expandable member 1110, and proximal endof conduit 1128 does not extend as far proximally as proximal end 1121of first expandable member 1108.

When the disclosure herein refers to a conduit being coupled to anexpandable member, the term coupled in this context does not requirethat the conduit be directly attached to the expandable member so thatconduit physically contacts the expandable member. Even if not directlyattached, however, the term coupled in this context refers to theconduit and the expandable member being joined together such that as theexpandable member expands or collapses, the conduit also begins totransition to a different configuration and/or size. Coupled in thiscontext therefore refers to conduits that will move when the expandablemember to which it is coupled transitions between expanded and collapsedconfigurations.

Any of the conduits herein can be deformable to some extent. Forexample, conduit 1112 includes elongate member 1120 that can be made ofone or more materials that allow the central region 1113 of conduit todeform to some extent radially inward (towards LA) in response to, forexample and when in use, forces from valve tissue (e.g., leaflets) or areplacement valve as working portion 1104 is deployed towards theconfiguration shown in FIG. 17. The conduit may be stretched tightlybetween the expandable members in some embodiments. The conduit mayalternatively be designed with a looseness that causes a greater degreeof compliance. This can be desirable when the working portion isdisposed across fragile structures such as an aortic valve, which mayallow the valve to compress the conduit in a way that minimizes pointstresses in the valve. In some embodiments, the conduit may include amembrane attached to the proximal and distal expandable members.Exemplary materials that can be used for any conduits herein include,without limitations, polyurethane rubber, silicone rubber, acrylicrubber, expanded polytetrafluoroethylene, polyethylene, polyethyleneterephthalate, including any combination thereof.

Any of the conduits herein can have a thickness of, for example, 0.5-20thousandths of an inch (thou), such as 1-15 thou, or 1.5 to 15 thou, 1.5to 10 thou, or 2 to 10 thou.

Any of the conduits herein, or at least a portion of the conduit, can beimpermeable to blood. In FIG. 17, working portion 1104 includes a lumenthat extends from distal end 1126 of conduit 1112 and extends toproximal end 1128 of conduit 1112. The lumen is defined by conduit 1112in central region 1113, but can be thought of being defined by both theconduit and portions of the expandable members in regions axiallyadjacent to central region 1113. In this embodiment, however, it is theconduit material that causes the lumen to exist and prevents blood frompassing through the conduit.

Any of the conduits herein that are secured to one or more expandablemembers can be, unless indicated to the contrary, secured so that theconduit is disposed radially outside of one or more expandable members,radially inside of one or more expandable members, or both, and theexpandable member can be impregnated with the conduit material.

The proximal and distal expandable members help maintain the conduit inan open configuration to create the lumen, while each also creates aworking environment for an impeller, described below. Each of theexpandable members, when in the deployed configuration, is maintained ina spaced relationship relative to a respective impeller, which allowsthe impeller to rotate within the expandable member without contactingthe expandable member. Working portion 1104 includes first impeller 1116and second impeller 1118, with first impeller 1116 disposed radiallywithin first expandable member 1108 and second impeller 1118 disposedradially within second expandable member 1110. In this embodiment, thetwo impellers even though they are distinct and separate impellers, arein operable communication with a common drive mechanism (e.g., drivecable 1117), such that when the drive mechanism is activated the twoimpellers rotate together. In this deployed configuration, impellers1116 and 1118 are axially spaced apart along longitudinal axis LA, justas are the expandable members 1108 and 1110 are axially spaced apart.

Impellers 1116 and 1118 are also axially within the ends of expandablemembers 1108 and 1110, respectively (in addition to being radiallywithin expandable members 1108 and 1110). The impellers herein can beconsidered to be axially within an expandable member even if theexpandable member includes struts extending from a central region of theexpandable member towards a longitudinal axis of the working portion(e.g., tapering struts in a side view). In FIG. 17, second expandablemember 1110 extends from first end 1124 (proximal end) to second end1125 (distal end).

In FIG. 17, a distal portion of impeller 1118 extends distally beyonddistal end 1126 of conduit 1112, and a proximal portion of impeller 1116extends proximally beyond proximal end 1128 of conduit 1112. In thisfigure, portions of each impeller are axially within the conduit in thisdeployed configuration.

In the exemplary embodiment shown in FIG. 17, impellers 1116 and 1118are in operable communication with a common drive mechanism 1117, and inthis embodiment, the impellers are each coupled to drive mechanism 1117,which extends through shaft 1119 and working portion 1104. Drivemechanism 1117 can be, for example, an elongate drive cable, which whenrotated causes the impellers to rotate. In this example, as shown, drivemechanism 1117 extends to and is axially fixed relative to distal tip1114, although it is adapted to rotate relative to distal tip 1114 whenactuated. Thus, in this embodiment, the impellers and drive mechanism1117 rotate together when the drive mechanism is rotated. Any number ofknown mechanisms can be used to rotate drive mechanism, such as with amotor (e.g., an external motor).

The expandable members and the conduit are not in rotational operablecommunication with the impellers and the drive mechanism. In thisembodiment, proximal end 1121 of proximal expandable member 1108 iscoupled to shaft 1119, which may be a shaft of elongate portion 1106(e.g., an outer catheter shaft). Distal end 1122 of proximal expandablemember 1108 is coupled to central tubular member 1133, through whichdrive mechanism 1117 extends. Central tubular member 1133 extendsdistally from proximal expandable member 1108 within conduit 1112 and isalso coupled to proximal end 1124 of distal expandable member 1110.Drive mechanism 1117 thus rotates within and relative to central tubularmember 1133. Central tubular member 1133 extends axially from proximalexpandable member 1108 to distal expandable member 1110. Distal end 1125of distal expandable member 1110 is coupled to distal tip 1114, asshown. Drive mechanism 1117 is adapted to rotate relative to tip 1114,but is axially fixed relative to tip 1114.

Working portion 1104 is adapted and configured to be collapsed to asmaller profile than its deployed configuration (which is shown in FIG.17). This allows it to be delivered using a lower profile deliverydevice (smaller French size) than would be required if none of workingportion 1104 was collapsible. Even if not specifically stated herein,any of the expandable members and impellers may be adapted andconfigured to be collapsible to some extent to a smaller deliveryconfiguration.

The working portions herein can be collapsed to a collapsed deliveryconfiguration using conventional techniques, such as with an outersheath that is movable relative to the working portion (e.g., by axiallymoving one or both of the sheath and working portion). For examplewithout limitation, any of the systems, devices, or methods shown in thefollowing references may be used to facilitate the collapse of a workingportions herein: U.S. Pat. No. 7,841,976 or 8,052,749, the disclosuresof which are incorporated by reference herein.

FIGS. 18A-18E show an exemplary working portion that is similar in someways to the working portion shown in FIG. 17. Working portion 340 issimilar to working portion 1104 in that in includes two expandablemembers axially spaced from one another when the working portion isexpanded, and a conduit extending between the two expandable members.FIG. 18A is a perspective view, FIG. 18B is a side sectional view, andFIGS. 18C and 18D are close-up side sectional views of sections of theview in FIG. 18B.

Working portion 340 includes proximal impeller 341 and distal impeller342, which are coupled to and in operational communication with a drivecable, which defines therein a lumen. The lumen can be sized toaccommodate a guidewire, which can be used for delivery of the workingportion to the desired location. The drive cable, in this embodiment,includes first section 362 (e.g., wound material), second section 348(e.g., tubular member) to which proximal impeller 341 is coupled, thirdsection 360 (e.g., wound material), and fourth section 365 (e.g.,tubular material) to which distal impeller 342 is coupled. The drivecable sections all have the same inner diameter, so that lumen has aconstant inner diameter. The drive cable sections can be secured to eachother using known attachment techniques. A distal end of fourth section365 extends to a distal region of the working portion, allowing theworking portion to be, for example, advanced over a guidewire forpositioning the working portion. In this embodiment the second andfourth sections can be stiffer than first and third sections. Forexample, second and fourth can be tubular and first and third sectionscan be wound material to impart less stiffness.

Working portion 340 includes proximal expandable member 343 and distalexpandable member 344, each of which extends radially outside of one ofthe impellers. The expandable members have distal and proximal ends thatalso extend axially beyond distal and proximal ends of the impellers,which can be seen in FIGS. 18B-18D. Coupled to the two expandablemembers is conduit 356, which has a proximal end 353 and a distal end352. The two expandable members each include a plurality of proximalstruts and a plurality of distal struts. The proximal struts in proximalexpandable member 343 extend to and are secured to shaft section 345,which is coupled to bearing 361, through which the drive cable extendsand is configured and sized to rotate. The distal struts of proximalexpandable member 343 extend to and are secured to a proximal region (toa proximal end in this case) of central tubular member 346, which isdisposed axially in between the expandable members. The proximal end ofcentral tubular member 346 is coupled to bearing 349, as shown in FIG.18C, through which the drive cable extends and rotates. The proximalstruts of distal expandable member 344 extend to and secured to a distalregion (to a distal end in this case) of central tubular member 346.Bearing 350 is also coupled to the distal region of central tubularmember 346, as is shown in FIG. 18D. The drive cable extends through androtates relative to bearing 350. Distal struts of distal expandablemember extend to and are secured to shaft section 347 (see FIG. 18A),which can be considered part of the distal tip. Shaft section 347 iscoupled to bearing 351 (see FIG. 18D), through which the drive cableextends and rotates relative to. The distal tip also includes bearing366 (see FIG. 18D), which can be a thrust bearing. Working portion 340can be similar to or the same in some aspects to working portion 1104,even if not explicitly included in the description. In this embodiment,conduit 356 extends at least as far as ends of the impeller, unlike inworking portion 1104. Either embodiment can be modified so that theconduit extends to a position as set forth in the other embodiment. Insome embodiments, section 360 can be a tubular section instead of wound.

While specific exemplary locations may be shown herein, the fluid pumpsmay be able to be used in a variety of locations within a body. Someexemplary locations for placement include placement in the vicinity ofan aortic valve or pulmonary valve, such as spanning the valve andpositioned on one or both sides of the valve, and in the case of anaortic valve, optionally including a portion positioned in the ascendingaorta. In some other embodiments, for example, the pumps may be, in use,positioned further downstream, such as being disposed in a descendingaorta.

FIG. 19 illustrates an exemplary placement of working portion 1104 fromsystem 1000 from FIG. 17. One difference shown in FIG. 19 is that theconduit extends at least as far as the ends of the impellers, like inFIGS. 18A-18D. FIG. 19 shows working portion 1104 in a deployedconfiguration, positioned in place across an aortic valve. Workingportion 1104 can be delivered as shown via, for example withoutlimitation, femoral artery access (a known access procedure). While notshown for clarity, system 1000 can also include an outer sheath or shaftin which working portion 1104 is disposed during delivery to a locationnear an aortic valve. The sheath or shaft can be moved proximally(towards the ascending aorta “AA” and away from left ventricle “LV) toallow for deployment and expansion of working portion 1104. For example,the sheath can be withdrawn to allow for expansion of second expandablemember 1110, with continued proximal movement allowing first expandablemember 1108 to expand.

In this embodiment, second expandable member 1110 has been expanded andpositioned in a deployed configuration such that distal end 1125 is inthe left ventricle “LV,” and distal to aortic valve leaflets “VL,” aswell as distal to the annulus. Proximal end 1124 has also beenpositioned distal to leaflets VL, but in some methods proximal end 1124may extend slightly axially within the leaflets VL. This embodiment isan example of a method in which at least half of the second expandablemember 1110 is within the left ventricle, as measured along its length(measured along the longitudinal axis). And as shown, this is also anexample of a method in which the entire second expandable member 1110 iswithin the left ventricle. This is also an example of a method in whichat least half of second impeller 1118 is positioned within the leftventricle, and also an embodiment in which the entire second impeller1118 is positioned within the left ventricle.

Continued retraction of an outer shaft or sheath (and/or distal movementof working end 1104 relative to an outer sheath or shaft) continues torelease conduit 1112, until central region 1113 is released anddeployed. The expansion of expandable members 1108 and 1110 causesconduit 1112 to assume a more open configuration, as shown in FIG. 19.Thus, while in this embodiment conduit 1112 does not have the sameself-expanding properties as the expandable members, the conduit willassume a deployed, more open configuration when the working end isdeployed. At least a portion of central region 1113 of conduit 1112 ispositioned at an aortic valve coaptation region. In FIG. 18, there is ashort length of central region 1113 that extends distally beyond theleaflets VL, but at least some portion of central region 1113 is axiallywithin the leaflets.

Continued retraction of an outer shaft or sheath (and/or distal movementof working end 1104 relative to an outer sheath or shaft) deploys firstexpandable member 1108. In this embodiment, first expandable member 1108has been expanded and positioned (as shown) in a deployed configurationsuch that proximal end 1121 is in the ascending aorta AA, and proximalto leaflets “VL.” Distal end 1122 has also been positioned proximal toleaflets VL, but in some methods distal end 1122 may extend slightlyaxially within the leaflets VL. This embodiment is an example of amethod in which at least half of first expandable member 1110 is withinthe ascending aorta, as measured along its length (measured along thelongitudinal axis). And as shown, this is also an example of a method inwhich the entire first expandable member 1110 is within the AA. This isalso an example of a method in which at least half of first impeller1116 is positioned within the AA, and also an embodiment in which theentire first impeller 1116 is positioned within the AA.

At any time during or after deployment of working portion 1104, theposition of the working portion can be assessed in any way, such asunder fluoroscopy. The position of the working portion can be adjustedat any time during or after deployment. For example, after secondexpandable member 1110 is released but before first expandable member1108 is released, working portion 1104 can be moved axially (distally orproximally) to reposition the working portion. Additionally, forexample, the working portion can be repositioned after the entireworking portion has been released from a sheath to a desired finalposition.

It is understood that the positions of the components (relative to theanatomy) shown in FIG. 19 are considered exemplary final positions forthe different components of working portion 1104, even if there wasrepositioning that occurred after initial deployment.

The one or more expandable members herein can be configured to be, andcan be expanded in a variety of ways, such as via self-expansion,mechanical actuation (e.g., one or more axially directed forces on theexpandable member, expanded with a separate balloon positioned radiallywithin the expandable member and inflated to push radially outward onthe expandable member), or a combination thereof.

Expansion as used herein refers generally to reconfiguration to a largerprofile with a larger radially outermost dimension (relative to thelongitudinal axis), regardless of the specific manner in which the oneor more components are expanded. For example, a stent that self-expandsand/or is subject to a radially outward force can “expand” as that termis used herein. A device that unfurls or unrolls can also assume alarger profile, and can be considered to expand as that term is usedherein.

The impellers can similarly be adapted and configured to be, and can beexpanded in a variety of ways depending on their construction. Forexamples, one or more impellers can, upon release from a sheath,automatically revert to or towards a different larger profileconfiguration due to the material(s) and/or construction of the impellerdesign (see, for example, U.S. Pat. No. 6,533,716, or U.S. Pat. No.7,393,181, both of which are incorporated by reference herein).Retraction of an outer restraint can thus, in some embodiments, allowboth the expandable member and the impeller to revert naturally to alarger profile, deployed configuration without any further actuation.

As shown in the example in FIG. 19, the working portion includes firstand second impellers that are spaced on either side of an aortic valve,each disposed within a separate expandable member. This is in contrastto some designs in which a working portion includes a single elongateexpandable member. Rather than a single generally tubular expandablemember extending all the way across the valve, working end 1104 includesa conduit 1112 extending between expandable members 1108 and 1110. Theconduit is more flexible and deformable than the expandable baskets,which can allow for more deformation of the working portion at thelocation of the leaflets than would occur if an expandable memberspanned the aortic valve leaflets. This can cause less damage to theleaflets after the working portion has been deployed in the subject.

Additionally, forces on a central region of a single expandable memberfrom the leaflets might translate axially to other regions of theexpandable member, perhaps causing undesired deformation of theexpandable member at the locations of the one or more impellers. Thismay cause the outer expandable member to contact the impeller,undesirably interfering with the rotation of the impeller. Designs thatinclude separate expandable members around each impeller, particularlywhere each expandable member and each impeller are supported at bothends (i.e., distal and proximal), result in a high level of precision inlocating the impeller relative to the expandable member. Two separateexpandable members may be able to more reliably retain their deployedconfigurations compared with a single expandable member.

As described herein above, it may be desirable to be able to reconfigurethe working portion so that it can be delivered within a 9F sheath andstill obtain high enough flow rates when in use, which is not possiblewith some products currently in development and/or testing. For example,some products are too large to be able to be reconfigured to a smallenough delivery profile, while some smaller designs may not be able toachieve the desired high flow rates. An exemplary advantage of theexamples in FIGS. 16, 17, 18A-18D and 19 is that, for example, the firstand second impellers can work together to achieve the desired flowrates, and by having two axially spaced impellers, the overall workingportion can be reconfigured to a smaller delivery profile than designsin which a single impeller is used to achieved the desired flow rates.These embodiments thus use a plurality of smaller, reconfigurableimpellers that are axially spaced to achieve both the desired smallerdelivery profile as well as to achieve the desired high flow rates.

The embodiment herein can thus achieve a smaller delivery profile whilemaintaining sufficiently high flow rates, while creating a moredeformable and flexible central region of the working portion, theexemplary benefits of which are described above (e.g., interfacing withdelicate valve leaflets).

FIGS. 20A, 20B, and 20C illustrate exemplary distal end constructionsand configurations for a working portion, and can be incorporated intoany of the working portions herein or other working portions known inthe art. FIGS. 20A-C illustrate exemplary distal tip features that mayhelp facilitate blood flow and facilitate proper positioning across theaortic valve if the tip is positioned against a flow-blocking structuresuch as the apex of the left ventricle.

FIG. 20A illustrates an exemplary working portion 1502 with inflowapertures 1508 and outflow apertures 1510, and distal tip 1504 withdistal end 1506. Tip 1504 can have a pigtail configuration withsufficient strength to prevent collapse when pushed against heart tissuesuch as left ventricular tissue. Tip 1504 could also include a stifferinternal wire (stiffer than the outer material of the distal tip).

FIG. 20B illustrates an exemplary working portion 1512 that includes tip1516 and inflow portion 1514 adjacent and proximal to tip 1516. Inflowportion 1514 includes a plurality of elements 1518 that define aplurality of apertures that allow sufficient blood flow even pushedagainst heart tissue, such as left ventricular tissue. Inflow portion1514 can be configured like a stent or stent-like device created byweaving or braiding wire or laser cutting a tubular member. Inflowportion 1514 can be comprised of, for example, self-expanding materialsuch as nitinol.

FIG. 20C illustrates exemplary working portion 1520 that includes tip1524 with first plurality of inflow openings 1526 with a first generalconfiguration, and second plurality of inflow openings 1522 with asecond general configuration different than the first generalconfiguration. The plurality of openings are configured to allowsufficient blood flow even when the tip is pushed against heart tissue.

In any embodiment, a plurality of inflow openings or apertures may bemolded into the design of a tip piece that is attached to the rest ofthe working portion by adhesive, solvent welding, ultrasonic welding,laser welding or using a similar process. Additional holes can be addednear a bonded tip using, for example without limitation, core drillingor laser machining.

FIG. 21A illustrates an exemplary position of deployed working portion1520, wherein the length of working portion is such that a properposition across an aortic valve is achieved by urging the workingportion forward until it engages left ventricular (LV) tissue, as shown.In this position, inflow inlets 1522 and 1526 are in the left ventricle,and outflow apertures 1528 are disposed in the ascending aorta, and acentral region of working portions extends along the aortic valveleaflets VL.

FIGS. 21B and 21C illustrate alternative distal regions of a workingportion that do not include a pigtail configuration like in 20A-20C and21A. These tip regions can be incorporated into any suitable workingportion herein, or any other working portion known in the art. FIG. 21Billustrates an exemplary tip region that includes an expandable member1612, such as a self-expanding stent-like structure, which can be formedlike any expandable member herein. Expandable member 1612 has aplurality of elongate elements that define a plurality of inflowopenings. The openings define sufficient open space to preventrestriction of blood flow and minimize hemolysis while also allowingadequate blood flow even if member 1612 is pushed against a structuresuch as a wall of the left ventricle or even the apex of the leftventricle. Member 1612 can have a variety of configurations, such as,for example, a teardrop-shape or round shape (e.g., length equal todiameter, or up to several times the diameter). Member 1612 is in thisembodiment at the distal most end of the working portion.

FIG. 21C illustrates a portion of an exemplary working portion thatincludes distal tip 1602 that includes inlet openings 1604 and one ormore inflatable members 1619 at the distal most end of the workingportion. The inflatable member(s) 1619 are at the distal most end of theworking portion. An inflatable tip, such as shown in FIG. 21C, could beroughly spherical, or optionally teardrop-shaped, so the more proximalend has minimal or no features that could catch on cordae tendinae orsimilar structures within the heart, or other features near blood vesselbranches or other such hollow anatomical structure features.

Impellers herein are adapted to be collapsed from deployed, expandedconfigurations to collapsed, smaller outer dimension configurations,unless indicated to the contrary. This helps minimize the deliveryprofile for the overall working portion, and yet expand to a greaterouter dimension size that can help generate the desired flow rate.

FIGS. 22A and 22B illustrate end views of an exemplary impeller 1701,with blades 1720 in collapsed configurations (FIG. 22A) and expandedconfigurations (FIG. 22B). The impeller includes central member 1721from which blades 1720 extend radially. In the expanded configuration inFIG. 22B, the blades extend further radially outward relative to centralmember 1721. The blades can be made from materials that self-expand tolarger outer dimensions, such as polymeric materials (e.g.,polyethylene, polypropylene, polyester, ABS, nylon, acetal,polyphenylene sulfide), silicone, or a superelastic wireform with apolymer webbing, for example.

FIGS. 23A-C illustrate an exemplary impeller 1801, with blades 1820 eachincluding weighted elements 1822 therein. Weighted elements 1822 can beweight elements of higher density (e.g., tungsten, stainless steel) orregions that have greater thickness that the rest of the blade. In thelater embodiments, the elements 1822 can thus be part of the blade andnot a separate component. A greater density or greater thickness wouldcause the impeller blades to be pulled outward by centrifugal reaction,as seen by comparing the deployed configuration in FIG. 23B and theoperational configuration during rotation seen in FIG. 23C.

FIGS. 24A and 24B illustrate impeller 1901, with blades 1922 incollapsed and operational configurations, respectively. Impeller blades1922 are configured to catch the fluid flow in a way that thereactionary force of the blood pushing against the face of the bladesdrives the impeller blade to expand from the less-expanded shape to themore-expanded shape.

Some working portions herein can include a plurality of lumens, each ofwhich is a fluid lumen through which a fluid (e.g., blood) can flow.Dual lumen working portions can be used with, for example, dual-motordesigns. More than two lumens can be incorporated as well, and thus morethan two motors can also be incorporated. FIGS. 25A and 25B illustratean exemplary multi-lumen (lumens 1922 and 1924) working portion 1920 ina collapsed, delivery configuration (FIG. 25A) and an expandedconfiguration (FIG. 25B). The smaller, collapsed profile enables asmaller delivery profile, and yet can be expanded to a larger dimensionto allow for the desired higher flow rate, such as 4-6 L/min. Exemplaryways in which the lumens can be expanded include expansion of a braidedbasket structure, by inflation of the lumen by increased blood pressure,or a combination of both.

FIGS. 26A and 26B illustrates an exemplary multi-lumen design for aworking portion, showing deployed and expanded configurations,respectively. Working portion 50 includes an outer body 51 in which amatrix structure 52 is embedded, such as a braided structure. Septum 53extends across the interior of the working portion and extends radiallyinwards from outer body 51, dividing lumens 54 and 55. Septum 53 andouter body 51 are flexible, and stretch and become thinner (as shown) asthe outer body 51 expands from the collapsed smaller outer dimension tothe deployed larger outer dimension. The material(s) chosen will allowfor these properties. The outer profile in this embodiment in circular.

In some relevant embodiments, additional lumens to accommodate, forexample, motor wiring, fluid pressure measurement and/or a guidewire maybe included. FIGS. 27A-C illustrate exemplary embodiments with suchadditional lumens. FIG. 27A illustrates exemplary working portion withouter wall 60, septum 61, channel 62, lumen 63 defined by channel 62,first fluid lumen 64 and second fluid lumen 65. Lumen 63 and channel 62are within septum 61. In FIG. 26B, lumen 73 and channel 72 are disposedat an intersection between lumens 64 and 65. Working portion includeswall 70, septum 71, fluid lumen 74 and fluid lumen 75. FIG. 26C showschannel 82 and lumen 83 disposed at a periphery of wall 80 and adjacentseptum 81.

FIG. 28 illustrates an exemplary concept in which working portion 90includes expandable member 93, which includes a plurality of elongatesegments 92 (only one is labeled). Working portion 90 also illustrateshow wiring and/or lumen(s) 91 (only one is labeled but more than one canbe included for different purposes) can be incorporated into theexpandable member (e.g., a braided structure). Here, wire and/or lumen91 follows the periphery of the expandable member, in a curvilinearfashion, from a proximal portion to a distal portion. Other workingportion components (e.g., impeller(s), conduit) can of course beincorporated with expandable member 93. Expansion of the expandablemember does not stretch the wiring and/or lumen(s) in this embodiment.

This disclosure now describes some exemplary magnetic coupling designs,which can be incorporated with any suitable working portion and medicaldevice herein. The magnetic couplings are part of motors that can drivethe rotation of one or more impellers herein. FIG. 29 illustrates anexemplary fluid movement medical device 100, which includes workingportion 102, magnetic coupling 105, motor 108, shaft 113, and one ormore wires 109. An exemplary advantage of the embodiment in FIG. 29 isthat the motor can be re-used relatively easily for future procedures.Housing 114 houses motor 108, a distal portion of wires 109, shaft 113,and magnetic member 107. Working portion includes inflow end 101, tip104, impeller 112, and outlet openings 103. After use, working portion102 can be removed from housing 114, and housing 114 can be cut orsevered at optional cut zone 111. This separates the motor, allowing itto be reused. This design also allows for a blood-free motor, which maybe especially helpful for reuse of this component in devicereprocessing. Cut zone 111 can be created to facilitate the removal ofmotor 108 and associated wiring without damage.

FIG. 30 illustrates an exemplary magnetic coupling for a motor and drivecable. This magnetic coupling arrangement may be used near the proximalend of the medical device to provide an indirect-contact gap between adrive motor and a drive cable. This arrangement allows a sterile barrierto enclose a non-sterile handle unit that includes the drive motor in away that allows it to be magnetically coupled to a sterile cathetershaft connector. This provides an advantage that a non-sterile handleand cable assembly could be used and re-used in many medical procedureswithout need for cleaning, disinfection and sterilization as a multi-useassembly. A single-use catheter assembly that includes a workingportion, and a single-use sterile barrier could be used for eachprocedure.

FIG. 30 illustrates proximal coupling 122 between motor housing 128 andcatheter portion 123 of the medical device. Catheter portion 123includes any suitable working portion herein, or other working portionsknown in the art. Motor housing 128 includes motor 126 coupled tomagnetic member 125. Sterile sleeve 127 can be advanced over motorhousing 128. Catheter portion 123 includes magnetic member 124 and drivecable 121. Activation of the motor causes rotation of the drive cablevia magnetic coupling 122.

If a magnetic coupling is used with any of the medical devices herein, alarger torque lever arm may be needed. It may thus be advantageous for alarger magnetic coupler wheel to be mounted at a 90-degree angle to thecatheter shaft to allow for low-height (and therefore low-volume)packaging. FIG. 31 illustrates an embodiment of this, using a 90-degreegearset to couple to the drive cable. Only a portion of the device isshown in FIG. 31 for clarity. Motor 133 is coupled to first magneticmember 131. Drive cable 135 and second magnetic member 132 are coupledto 90 degree gearset 134.

In some embodiments, a working portion can have a generally straight tipto allow for easy insertion into the body and then the tip is biasedinto a generally L-shape or J-shape to facilitate navigation and reducepotential trauma to intravascular or intracardiac structures. Thesecondary distal configuration can be accomplished by using of a stiffcurved member inserted into a working portion lumen, such as a guidewirelumen. Alternatively, a secondary distal configuration can beaccomplished by steerable catheter mechanisms, such as one or more pullwires within a wall of the working portion, near the distal tip. FIG.32A illustrates exemplary working portion 140, including lumen region141 and distal tip 142 in a generally straight configuration. FIG. 32Bshows internal elongate member 143, such as a guidewire, advancedthrough working portion 140 and into distal tip 142. The previouslystraight tip 142 durably assumes a, in this embodiment, “J”configuration.

FIGS. 33A-33E illustrate exemplary distal ends of working portions,which can be incorporated into any suitable working portion herein orother working portion known in the art. In FIG. 33A, working portion 190includes conduit 191 and expandable member 192. Expandable member 192includes a plurality of elongate elements, including tapering struts193, which extend from element 199 proximally. Struts 193 can beintegral to element 199 or can be coupled thereto. Struts 193 defineinlet apertures 195 (only one is labeled) for blood to flow into theworking portion lumen. The distal end of expandable member 192 includesfirst region 198 in which at which at least one aperture has a firstarea, second region 197, in which at least one aperture has anintermediate aperture, and third region 196, in which at least oneaperture has a third area, wherein the first area is greater than theintermediate area, and the intermediate area is greater than the thirdarea.

FIG. 33B is similar to FIG. 33A, the description of which isincorporated by reference into the description of FIG. 33B. Workingportion 220 includes struts 222, however, that extend radially outward,then radially inward. Working portion 220 also includes elongate member223, which can be coupled to an impeller, and interfaces element 224.

Working portion 230 in FIG. 36C is similar to FIGS. 33A and 33B, thedescriptions of which are incorporated by reference into the descriptionof FIG. 33C. Working portion 230, however, includes distal tip 231 witha curvilinear configuration and that includes a plurality of apertures232 therein. Tip 231 has distal end 233.

Working portion 240 in FIG. 33D is similar to FIGS. 33A-33C, thedescriptions of which are incorporated by reference into the descriptionof FIG. 33D. Working portion 240, however, includes struts 243 thattaper down and meet one another at the distal end of the workingportion. Working portion 240 does not have separate tip portion thatextends distally struts, as is the case in FIGS. 33A-C. Working portion240 also includes shaft 241 that is secured relative to member 242.

Working portion 250 in FIG. 33E is similar to FIGS. 33A-D, thedescriptions of which are incorporated by reference into the descriptionof FIG. 33E. Working portion 250, however, includes distal extension 251that has a round configuration, which can be spherical, toroidal,egg-shaped, etc. Distal extension 251 has a plurality of holes 253therein, and can be integrally formed with struts 254 via connectorportion 252.

FIG. 34 illustrates a working portion that is similar to the workingportion shown in FIG. 16. Working portion 265 includes proximal impeller266, distal impeller 267, both of which are coupled to drive shaft 278,which extends into distal bearing housing 272. There is a similarproximal bearing housing at the proximal end of the working portion.Working portion also includes expandable member, referred to 270generally, and conduit 268 that is secured to the expandable member andextends almost the entire length of expandable member. Expandable member270 includes distal struts 271 that extend to and are secured to strutsupport 273, which is secured to distal tip 273. Expandable member 270also includes proximal struts there are secured to a proximal strutsupport. All features similar to that shown in FIG. 16 are incorporatedby reference into this embodiment even if not explicitly stated.Expandable member 265 also includes helical tension member 269 that isdisposed along the periphery of the expandable member, and has a helicalconfiguration when the expandable member is in the expandedconfiguration as shown. The helical tension member 269 is disposed andadapted to induce rotation wrap upon collapse. Working portion 265 canbe collapsed from the shown expanded configuration while simultaneouslyrotating one or both impellers at a relatively slow speed to facilitatecurled collapse of the impellers due to interaction with the expandablemember. Helical tension member 269 (or a helical arrangement ofexpandable member cells) will act as a collective tension member and isconfigured so that when the expandable basket is pulled in tension alongits length to collapse (such as by stretching to a much greater length,such as approximately doubling in length) tension member 269 is pulledinto a straighter alignment, which causes rotation/twisting of thedesired segment(s) of the expandable member during collapse, whichcauses the impeller blades to wrap radially inward as the expandablemember and blades collapse. An exemplary configuration of such a tensionmember would have a curvilinear configuration when in helical form thatis approximately equal to the maximum length of the expandable memberwhen collapsed. In alternative embodiments, only the portion(s) of theexpandable member that encloses a collapsible impeller is caused torotate upon collapse.

There are alternative ways to construct the working portion to causerotation of the expandable member upon collapsed by elongate (and thuscause wrapping and collapse of the impeller blades). Any expandablemember can be constructed with this feature, even in dual-impellerdesigns. For example, with an expandable member that includes aplurality of “cells,” as that term is commonly known (e.g., a laser cutelongate member), the expandable member may have a plurality ofparticular cells that together define a particular configuration such asa helical configuration, wherein the cells that define the configurationhave different physical characteristics than other cells in theexpandable member. In some embodiments the expandable member can have abraided construction, and the twist region may constitute the entiregroup of wires, or a significant portion (e.g., more than half), of thebraided wires. Such a twisted braid construction may be accomplished,for example, during the braiding process, such as by twisting themandred the wires are braided onto as it is pulled along, especiallyalong the length of the largest-diameter portion of the braidedstructure. The construction could also be accomplished during a secondoperation of the construction process, such as mechanically twisting abraided structure prior to heat-setting the wound profile over a shapedmandrel.

FIG. 35 illustrates an alternative embodiment to any of themulti-impeller pump designs herein, in which there are two endsemi-rigid impellers 282 and a helical flexible wall 283 between theimpeller blades 285 that is configured with the same helical pitch asthe pitch of the blades that convey blood, which is similar to anArchimedes screw. In a further embodiment, there are a plurality ofradial supports along the length of the flexible wall that prevent itfrom collapsing onto the impeller drive shaft 286 as is the normaltendency for a flexible tube when twisted.

With any of the pigtail tips herein, the pigtail tips can have varyingwall thicknesses to facilitate different being properties. In anexemplary embodiment, for example, there is a thinner wall thickness ina distal-most region of the pigtail and a relatively thicker wallthickness in a region disposed proximal to the distal-most region.

FIG. 36 shows an exemplary pump console with display 290 that can beused with any of the fluid pumps herein. Console includes speed displayelement, impeller rotation indication element, estimated blood flow ratedisplay 293, sensor display 294 (e.g., blood pressure reading), andbattery icon, and fluid pump electronics and/or purge connection 295.

In some embodiments, the catheter electrical connections and fluidconnections are integrated into a single connector that is configured tointerface with the console, such as by, for example, magneticattraction. In alternative embodiments, the electrical connectionsinterface separately from fluid connections. In such an embodiment, theconnections may be adjacent each other to interface as a unified pair ofconnectors. In some embodiments, the console is adapted to sense whethereither or both connectors are properly and completely mated.

In some embodiments, fluid entrainment is used to direct blood flow,such as by injection of saline. Other exemplary fluids are dextrosesolution or blood. Entrainment is the transport of fluid across aninterface between two bodies of fluid by a shear induced turbulent flux,but it is important to minimize blood hemolysis that may be caused byturbulent flux.

The disclosure includes devices and methods for confirming properpositioning of the working portions herein. In some embodiments, forexample, one or more ultrasound crystals (e.g., a piezoelectric crystal)re included in any of the working portions herein. The ultrasoundcrystal(s) can be used to indicate fluid motion such as blood flow, andmay also be used to detect the motion of the aortic valve and/or themitral valve. Exemplary locations for such sensors are near the bloodoutflow port(s) of a working portion and near the blood inflow port(s)of the working portion. In a method of use, the direction and degree ofturbulence of blood flow can be measured by the sensor(s) and comparedagainst reference data to determine if the working portion is locatedwith the valve (e.g., aortic) between the blood inflow and outflowport(s). If the sensed information does not indicate proper placement,the working portions can be moved until the sensors sense indicators ofproper placement. Within the ascending aorta, blood will flow primarilyfrom the aortic valve toward the descending aorta. Conversely, withinthe ventricle there is much more varied or cyclical flow direction asthe ventricle cavity fills and is partly emptied with each compressionof the ventricle muscle. The motion of the aortic valve leaflets canalso present a recognizable pattern that can be recognized as anultrasound crystal is passed therethrough. These methods can be usedwith any of the methods herein.

In some embodiments, the medical device includes a miniature videocamera (e.g., coupled to the working portion or just proximal to theworking portion) to directly view the anatomy during working portionplacement and confirmation, and moved if desired. In exemplaryembodiments, one or more cameras is placed proximal to the outflowport(s) of the working portion so that the user can directly view thedistal end of the working portion as directed through the aortic valve.Visible markings that are disposed on the catheter shaft may furtherindicate that the catheter is placed preferably in relation to a valve,such as an aortic valve (e.g., the working portion can be located sothat the valve is between the blood inflow and outflow ports). In someembodiments, the video camera system is adapted to visualize through ablood-filled vessel such as the aorta, such as by radiation of awavelength with minimum of total optical losses through blood. Anexemplary wavelength is within the infrared spectrum. In someembodiments, the radiation of the wavelength is reflected andbackscattered at least partly by a cardiovascular or catheter surface,detecting all intensity signals of the reflected and backscatteredradiation, and processing the detected signals by selecting intensitysignals of radiation being backscattered by blood only, and subtractingthe selected intensity signals of radiation backscattered only by bloodfrom all detected intensity signals of reflected and backscatteredradiation, so as to reconstruct an image of the cardiovascular orcatheter surface using the intensity signals of difference obtained bysubtracting.

In any relevant embodiment herein, ferrofluid may be used as a bearingor seal to prevent blood from entering the working portion bearingsand/or the motor assembly. In some embodiments, Ferrofluid is containedin a separate reservoir or channel during gas sterilization of thedevice, and then released or injected into the magnetic field to fillthe intended space to act as a bearing and/or seal. In some embodiments,a reservoir(s) containing ferrofluid comprises a membrane that dissolveswith fluid contact such as by flushing the device with saline or byblood contact, so that when the membrane dissolves the ferrofluid isreleased into position.

In some embodiments, a drive motor in the handle can be cooled bythermoelectric cooler (TEC) with heat from the hot end of TEC dissipatedby cooling fins or fluid circulation. Alternatively, a drive motor in ahandle can be cooled by plurality of cooling fins exposed to air. Thecooling fins may have air driven across them by an air-driving fan.

In some embodiments, torque feedback can be used to determine if theblood inlet and outlet ports are positioned on opposite side of a valve,such as an aortic valve. An exemplary method of measuring torquefeedback is under direct observation of position and flow rate with theworking portion positioned across valve, and also with inlets/outletsfully within the ventricle/ascending aorta, to determine the torqueboundaries as a function of impeller rotation speed. These boundariescan be used to confirm that the inlets and outlets are on opposite sidesof the aortic valve.

In any of the relevant embodiments herein, the working portion may haveone or more fluid exit holes between a distal impeller and a proximalimpeller, such that the fluid exit holes may support cardiac arteries ina system where the distal impeller section is within the left ventricleand the proximal impeller system is within the ascending aorta.

The blood outflow end of working portions herein may include a filteradapted to catch thrombus and/or debris.

In some embodiments, a first impeller (e.g., a distal or proximalimpeller) can be fixedly secured to a drive cable and a second impeller(e.g., a distal or proximal impeller) can be configured to slide (e.g.,proximally or distally) along the drive cable when the system iscollapsed. The slidable impeller is, however, configured to bemechanically engaged with the fixed impeller when the system isexpanded. The mechanical engagement can be created by intermediatetubing with geared or slotted ends so that the intermediate tubingtransfers torque from the first impeller to the second impeller. Inalternate embodiments, three or more impellers can be similarlyconfigured where one impeller is attached to a drive cable and theremaining impellers are mechanically engaged with the attached impeller.

When any of the methods of delivery, positioning, and use are performed,any of the following additional steps can also be performed, in anycombination thereof. The following optional steps describe some clinicalsteps or processes that can be performed as part of a pVAD procedure.

An exemplary process that can be performed is to measure activatedclotting time (“ACT”) or partial thromboplastin time (“PTT”) to assessanticoagulation. In any of the embodiments herein, an ACT or PTT sensorcan be incorporated into or attached to a fluid-pumping device, such ason a working portion thereon. ACT and/or PTT can be measured during anyor all of the following time periods: before the fluid device isinserted, during fluid device use (e.g., every 4-8 hours), after fluidpump pemoval, and before sheath removal. When hemolysis occurs,hemoglobin and hematocrit decrease, haptoglobin decreases and plasmafree hemoglobin increases.

Another exemplary step that can be performed is to verify that no accesssite limb ischemia has occurred due to obstruction. In any of theembodiments herein, one or more sensors for blood flow rate can belocated on the fluid-pumping catheter or on an arterial or venous accesssheath.

Another exemplary step that can be performed is to assess an arterialaccess site regularly for bleeding or hematoma. In any of theembodiments herein, an arterial or venous access sheath can include oneor more sensors adapted to detect bleeding or hematoma at the vesselaccess site.

Another exemplary step that can be performed, depending on the deviceused and the method of positioning it, is to verify that the workingportion has been advanced properly and is positioned across valve (e.g.,see FIG. 18 showing positioning across an aortic valve). For example,fluoroscopy can be used to confirm proper position of a working portionin a left ventricle and across an aortic valve. Sensed pressure can alsobe used to verify proper positioning. For example, an assessment can beperformed on the ventricular and the aortic waveform. Additionally, athigher flow rates, or if ventricular function is poor, patient bloodflow may be non-pulsatile. The motor current signal can also be used todetermine proper positioning. For example, a motor current signalflattens if the working portion flow inlet and the flow outlet are inthe left ventricle or aorta, or if ventricular function is poor. Forexample, a process engine can monitor motor current for an atypicalpattern that has been correlated with recirculation of fluid from thepump flow outlet to the flow inlet. Additionally, the pump can beadapted to verify that there no suction in the ventricle.

Another exemplary step that can be performed is to assess for anindication of aortic valve damage. For example, one or more strain gaugesensors can be positioned on the working portion in a region where theworking spans a valve, such as an aortic valve.

Another exemplary step that can be performed is to sense a blood flowrate conveyed by the fluid pump. For example, one or more flow ratesensors can be part of a working portion of disposed on the deviceimmediately adjacent to a working portion. For example, an ultrasoundcrystal sensor can be placed on or within the device, such as on orwithin a working portion, and aligned to measure the flow of blood thatis propelled by the working portion. In addition to or alternatively, adoppler crystal can be used to measure the velocity of blood flowingwithin the working portion or exiting the working portion.

Another exemplary step that can be performed is to sense the speed ofrotation of one or more impellers, and correlate that with a blood flowrate.

Another exemplary step that can be performed is to verify, optionallyfrequently, that the patient has no hemodynamic instability. Forexample, a blood-pumping system can include a plurality ofelectrocardiogram leads to measure the conduction of electrical signalsthat indicate cardiac function such as the beating of the heart.

Another exemplary step that can be performed is to perform continuouscardiac output monitoring, which may be useful for patients withcardiogenic shock. For example, a fluid-pumping device, such as aworking portion, can include one or more sensors such as thermodilutionsensors to indicate cardiac ejection fraction and/or cardiac index.

In some uses, inotropic agents, such as dobutamine and milrinone, andvasopressors, such as dopamine and norepinephrine, may still be neededafter the fluid pump is placed to maintain a cardiac index of at least 2and systolic blood pressure at 90 mm Hg or higher.

If the patient requires interrogation of a permanent pacemaker orimplantable cardioverter defibrillator, the fluid pump console can beturned off for a few seconds while the signal is established. Forexample, all potential electrical contacts within a fluid-pump and thepatient are electrically isolated so that there is no potential forelectrical interference between the fluid-pump system and an activeimplanted electronic device such as a pacemaker or implantablecardiverter defibrillator.

Part of any of the methods herein is verification that there are nocomplications, such as no reflow, no hypotension, and no lethalarrhythmia.

In some embodiments, transthoracic echocardiography (TTE) can beperformed to assess, for example, left ventricular size and function.

In some embodiments, the patient positioning is taken into considerationof ventilation and thrombosis/ulcer prophylaxis.

In some uses, the temperature of a motor and/or cable can be monitoredto indicate blood ingress/charring.

In some embodiments, one or more strain sensors can be incorporated intoany of the expandable members, and can be used to gauge deployment ofthe expandable member.

What is claimed is:
 1. A method of deploying an intravascular blood pumpacross an aortic valve, comprising: advancing an intravascular bloodpump to a region of a heart valve, the intravascular blood pumpcomprising a distal expandable member, a distal impeller, a proximalexpandable member, a proximal impeller, and a conduit; deploying thedistal expandable member and the distal impeller each from collapseddelivery configurations to deployed configurations, the distal impellerdisposed axially and radially within the distal expandable member intheir deployed configurations; deploying the proximal expandable memberand the proximal impeller each from collapsed delivery configurations todeployed configurations, the proximal impeller disposed axially andradially within the proximal expandable member in their deployedconfigurations, wherein when the distal and proximal expandable membersare in their deployed configurations, they are axially spaced apart suchthat a proximal end of the distal expandable member is distal to adistal end of the proximal expandable member; positioning at least aportion of the distal expandable member in a left ventricle so that adistal end of the distal expandable member is distal to aortic valveleaflets; positioning at least a portion of the proximal expandablemember in an ascending aorta so that a proximal end of the proximalexpandable member is proximal to the aortic valve leaflets; positioninga central region of the intravascular blood pump to interface with theaortic valve leaflets, the central region of the intravascular bloodpump including a central region of the conduit, the central region ofthe intravascular blood pump more flexible than a blood pump distalregion that is distal to the central region of the intravascular bloodpump and more flexible than a blood pump proximal region that isproximal to the central region of the intravascular blood pump;positioning the central region of the conduit that is axially in betweenthe deployed distal expandable member and the deployed proximalexpandable member such that the central region is positioned tointerface with the aortic valve leaflets; maintaining the distalexpandable member, the proximal expandable member, and the centralregion of the conduit in their respective positions at the same time;and activating the distal and proximal impellers with a common rotatabledrive mechanism that extends through a catheter, through the proximalimpeller, between the proximal impeller and the distal impeller, throughthe distal impeller, and is coupled to the proximal and distalimpellers, to cause the proximal and distal impellers to rotate and movefluid from the left ventricle towards the ascending aorta, whereinpositioning the central region of the intravascular blood pump tointerface with the aortic valve leaflets further comprises positioning aregion of the common rotatable drive mechanism that is between theproximal impeller and the distal impeller across the aortic valveleaflets, wherein the region of the common rotatable drive mechanismthat is between the proximal impeller and the distal impeller is moreflexible than the common rotatable drive mechanism where it extendsthrough the proximal impeller and more flexible than the commonrotatable drive mechanism where it extends through the distal impeller.2. The method of claim 1, wherein positioning at least a portion of thedistal expandable member in a left ventricle comprises positioning theentire distal expandable member distal to aortic valve leaflets.
 3. Themethod of claim 1, wherein positioning at least a portion of theproximal expandable member in an ascending aorta comprises positioningthe entire proximal expandable member proximal to aortic valve leaflets.4. The method of claim 1, wherein the deploying steps comprise allowingthe distal expandable member and the proximal expandable member toself-expand.
 5. The method of claim 1, wherein the central region of theintravascular blood pump further includes a central expandable memberbetween the distal proximal member and the proximal expandable member.